Summary
Elucidation of the pathophysiological basis of platelet disorders in murine models
requires a reliable method for the frequent determinations of platelet counts in individual
mice. Here, we present a rapid, reproducible and accurate flow cytometric method for
enumeration of platelets that involves fluorescent staining of platelets in whole
blood with specific antibody and the addition of known numbers of fluorescent beads
for standardization of the sample volume. Analysis of platelets obtained by tail bleeding
indicated that this sampling procedure did not activate platelets, and that only five
microliters of blood were required for platelet counting. Using this method, we followed
platelet counts in mice infected with the relapsing fever spirochete Borrelia turicatae for 26 days, and found that this bacterium induces thrombocytopenia, a common manifestation
of human relapsing fever. Therefore, this method can be used to follow the number
and the activation state of circulating platelets from individual mice over extended
periods of time and is applicable to a wide range of murine models of platelet disorders.
Keywords
Platelets - thrombocytopenia - murine model - flow cytometry - relapsing fever
